Conventionally, for example, light emitting devices disclosed in the following Patent Literature 1 and Patent Literature 2 have been available as surface mounted light emitting devices having a light emitting element such as a light emitting diode (LED) installed on a substrate surface and sealed with a transparent resin.
FIG. 7 is a longitudinal sectional view showing an example of a configuration of a conventional LED illumination module disclosed in Patent Literature 1.
As shown in FIG. 7, an LED illumination module 100 comprises a flexible wiring substrate made by forming a circuit wiring 102 on a flexible substrate 101, forming a flexible substrate 104 thereon with an adhesive 103 interposed therebetween, and forming a flexible reflection layer thereon for reflecting light from an LED die 105.
The module has a structure in which a heat spreader 107 penetrating the flexible wiring substrates 101 and 104 is provided, the LED die 105 is installed on the heat spreader 107, and an electrode on the top surface side of the LED die 105 is connected to an exposed surface of the circuit wiring 102 through an opening provided on the flexible substrate 104 with a wire 108 by wire bonding.
FIG. 8 is a longitudinal sectional view showing an example of a configuration of a conventional LED illumination module disclosed in Patent Literature 2.
As shown in FIG. 8, an LED illumination module 200 has an electrical insulator 201 (201a: adhesive layer, 201b: base material, and 201c: white insulator) with a total reflectance of light from at least the first surface side (wavelength 450 nm) of 80% or greater, via holes 202-204 that penetrate the electrical insulator 201, wiring patterns 205-207 provided on the second surface side of the electrical insulator 201, a wiring pattern 208 provided in the via hole 202, a wiring pattern 209 provided in the via hole 203, and a metal filled section 210 provided in the via hole 204.
An LED chip 211 is bonded to the first surface side of the electrical insulator 201 and the surface of the metal filled section 210 by die bonding. In addition, each electrode of the LED chip 211 is bonded to the wiring patterns 208 and 209 with a wire 212 by wire bonding. The LED chip 211 is then sealed by a resin with a resin sealing material 213.